JP2942296B2 - Electric zoom device - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an electric zoom device that changes the focal length of a lens by a motor, and more particularly to speed adjustment of the zoom device. .

[Problems to be Solved by the Related Art and the Invention] Conventionally, a camera having a power zoom mechanism that changes a focal length by driving a zoom lens by a motor has been used.

The power zoom operation is generally performed using a switch that can be operated in both directions with the neutral position in between. In addition, there is a device in which a plurality of switch positions are provided on both sides of a neutral position as a boundary, and the zoom speed can be switched depending on the operation position.

In the conventional electric zoom device, the switching position of the switch is small, so that the speed is switched in about two steps, and the zoom speed is uniquely determined according to the absolute position of the switching position.

However, when the switching position of the zoom switch is increased in order to enhance the operability of the zoom, if the switching position is uniquely associated with the zoom speed as described above, after the switch is largely operated from the neutral position, Since it takes time to return the switch to the neutral position, it cannot be stopped immediately.

Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides an electric zoom apparatus including a lesbian driving means for changing a focal length of a zoom lens, wherein telephoto and wide are used before zoom driving is started. Can be operated in both directions based on a neutral position as a boundary between the zoom lens and the operation start position before the start of driving the zoom lens as an operation initial position, and any one of the tele and the wide from the neutral position. Operating means for defining a stop position when operating and stopping in one direction; controlling the drive direction and drive speed of the lens drive means based on the operation initial position and the stop position; After the zoom lens is driven by the operation of the means in the one direction, the operation means is inverted in the direction toward the neutral position to switch between the neutral position and the stop position. In temporarily stopping the driving of the zoom lens at the time of stopping,
When the operating means is again stopped by performing the re-inverting operation in the one direction, the middle position of the operating means is redefined as an initial operation position, and the zoom lens is defined based on the initial operation position and the stop position. And control means for controlling the driving speed at a speed different from the driving speed.

Embodiment An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 schematically shows the entire configuration of a camera system including a body and a detachable lens.

The body 1 is a main CP that performs various information processing for shooting.
It has two CPUs, a U10 and a display CPU 11, which mainly performs information input by a switch, exchanges information with the photographing lens 2 and displays the information.

The display CPU 11 has an LCD panel 1 for displaying various information.
2. A Dx code input circuit 13 for inputting the ISO sensitivity of the film used from the Dx code printed on the patrone is connected. Further, the main CPU 10 is connected via an A / D circuit 15 to a light receiving element 14 for measuring the brightness of a subject from a light beam incident via a shooting lens, and a shutter based on various input shooting conditions. Exposure control circuit 16, which controls the CCD, CCD processing circuit 18, which detects the focusing state of the taking lens from the output of the CCD 17 for auto focus (AF),
An AF motor control circuit 20 for driving an AF motor 19 for focusing the lens, and an AF pulser 21 for detecting a drive amount of the AF motor as a pulse are connected.

The AF motor 19 is a coupler 19a
The driving force is transmitted to the photographing lens through the lens.

The battery 22 supplies power to each of the active elements in the camera body described above, and also includes a motor and a CPU in the taking lens.
Power is also supplied to

The lens 2 has a lens CPU 30 that exchanges information with the body side or processes information in the lens.

The lens includes a focus mechanism 31 for performing focusing by relatively moving each lens group in the optical axis direction by rotation of a cam ring, and a zoom mechanism 32 for performing zooming. The focus mechanism is connected to the coupler 19a when the lens is mounted on the body, focus operation is performed by obtaining driving force from the body side, and manual operation by releasing engagement with the coupler. Is also possible. The zoom mechanism 32 can be driven by a PZ motor 34 connected to a lens CPU via a power zoom (PZ) motor drive circuit 33, and can select both manual operation and motor drive by switching described below. It has a configuration.

As information input means to the lens CPU 30, a PZ pulser 35 for detecting a drive amount of the PZ motor as a pulse, a distance code plate 36 for inputting position information of the lens set by the focus mechanism, and a lens set by the zoom mechanism A zoom code plate 37 for inputting a focal length, and a zoom operation code plate 38 for inputting information regarding the direction and speed of the power zoom by operating a zoom operation ring are provided.

Incidentally, the code plate is actually constituted by a combination of a code plate fixed to the cam ring and a plurality of brushes attached to the fixed ring and slidably in contact with the code plate. Although the rotation position is detected, these are collectively shown as a code plate for convenience.

Also, lens-specific information such as the open F-number is stored in the ROM in the lens CPU, and the lens RO
It is not necessary to provide M independently.

__ <Body Circuit> Next, the block diagram will be described with reference to a more detailed circuit diagram.

 FIG. 2 shows the circuit of the body 1.

The voltage of the battery 22 is transformed by the regulator 23 and the super capacitor 24
And supplied at a low voltage.

The P1 terminal of the display CPU 11 turns on the power of the main CPU 10.
The photometering switch SW is connected to the DC / DC converter 25 that turns on and off, and the P2 terminal turns on when the shutter button is pressed one step down.
The S and P3 terminals are connected to a release switch SWR that is turned on when the shutter button is pressed in two steps, and the P4 terminal is connected to a lock switch SWL that is turned on when the camera is in a shooting state, and data of each switch is input. The DC / DC converter 25 operates according to a command from the display CPU when the photometric switch SWS or the release switch SWR is turned on while the lock switch SWL is turned on, and when inputting data on the lens side, and is executed by the main CPU 10. Power is supplied to the VDD terminal of this to operate it.

Furthermore, when the P5 terminal of the display CPU is turned on,
Mode switch SWM that enables selection of shooting mode such as auto shooting, manual shooting, etc.Drive switch SW that enables selection of single shooting, continuous shooting, etc. when the P6 terminal is ON
The Dr and P7 terminals are connected to an exposure compensation switch SWXv that enables the exposure compensation set when turned on.
By operating the up-count switch SWUp connected to the P8 terminal or the down-count switch SWDn connected to the P9 terminal while the switches connected to P5 to P7 are ON, the respective settings can be changed.

The PSEG terminal group is for driving the LCD panel 12, and displays various data necessary for photographing when the lock switch SWL is turned on.

The P10 terminal of the display CPU 11 is the Fmin1 contact on the body side, the P11 terminal is the Fmin2 contact on the body side, the P12 terminal is the Fmin3 contact on the body side, P
13 terminals are body-side Fmax1 contacts, P14 terminals are body-side Fmax2
Contact, P15 terminal is body A / M contact, P16 terminal is body side C
The ont contact, the P17 terminal are connected to the body side Vdd contact, and the P18 terminal is connected to the switch circuit 26, respectively.

Further, the switch circuit 26 is connected to the H (High) / L (Lo) of the P18 terminal.
The switching between the body-side VBatt contact and the battery 22 is performed by w), and the body-side Gnd contact is connected to the ground side of the battery 22 together with the Gnd terminal of the display CPU 11.

The display CPU 11 and the main CPU 10 transfer data via the serial clock terminal SCK, the serial in terminal SI, and the serial out terminal SO using the instruction codes shown in Table 1. The left column of Table 1 shows codes output from the display CPU to the main CPU.
M, set according to lens CPU data. The right column shows data input from the main CPU to the display CPU.
It is set based on measurement data of a photometry, a distance measuring device, and the like controlled by the CPU.

The PA contact group of the main CPU 10 is connected to the A / D circuit 15 for photometry, the PB contact group is an exposure control circuit 16, and the PC contact group is a CCD.
The processing circuit 18, the PD contact group are connected to the AF motor control circuit 20, the PE contact group is connected to the AF pulser 21, and the PF contact group is connected to the Dx input circuit 13. Note that the A / D circuit 15 is connected to the light receiving element 14 for photometry, the CCD processing circuit 18 is connected to the AF CCD 17, and the AF motor control circuit 19 is connected to the AF motor 19 in the body. It is as follows.

In addition, the P20 terminal of the main CPU10 uses AF for focusing.
Connected to the first AF switch SWAF1, which switches between auto mode by motor driving and manual mode by user manual driving, the P21 terminal switches the shutter release mode between focusing priority and release priority second AF Connected to Switch SWAF2. The first and second AF switches are configured to be mechanically linked, and when the first AF switch is set to the manual mode, the second AF switch has a release priority.

__ <Lens Circuit> FIG. 3 shows a circuit in the lens 2.

First, the connection state of each circuit, switch, and lens CPU 30 will be described.

The PZ motor drive unit 33 is connected to and controlled by the PH terminal group of the lens CPU 30, and the pulsar 35 is connected to the P20 terminal and inputs a detected motor drive amount to the lens CPU. Configuration.

The P21 to P29 terminals of the lens CPU 30 are provided on the lens side and switch the autofocus between automatic and manual.
Switch SWAF3, Zoom switch SWPZ1 to select whether to perform zooming automatically or manually by motor, Constant image magnification control to automatically perform zooming with relative movement to the subject so as to maintain the image magnification of the subject , An image magnification switch SWPZ2, and six switches of a zoom operation code plate for instructing the rotation direction and speed of the PZ motor 34 are connected respectively.
This switch will be described later.

Furthermore, the distance code plate is attached to the PI and PJ terminals of the lens CPU30.
36 and the zoom code plate 371 are connected, and the focal length information and the distance information corresponding to the actual lens state are input.

 Next, the contact point with the body will be described.

These contacts are connected to contacts of the same name on the body side when the lens is mounted on the body. In this system, a Vdd terminal is provided on the body side so as to be compatible with a conventional lens, but no corresponding contact is provided on the lens side.

The lens-side VBatt contact is connected to a PZ motor driving unit 33, and power is directly supplied from the battery 22 in the camera body to the PZ motor 34 by switching of the driving unit.

The lens side A / M contact 89 is connected to the ground potential line connected to the lens side Gnd contact via the aperture switch SWA / M, which switches the aperture between auto and manual by rotating the aperture ring on the lens side. I have.

The contact points Fmax1 and Fmax2 on the lens side are grounded via fuse setting sections H1 and H2 as fixed information sections similar to those provided in a conventional AE lens described later. Provides F-number information to the body.

The contacts Fmin1, 2, 3 on the lens side provide information of the open F-number in 3 bits and are also used as input / output terminals for the lens CPU. For this sharing, PNP transistors Tr1 to Tr3 are connected to these contacts. The emitter of each transistor is connected to the Fmin1,2,3 contacts, the base is connectable to the CONT contact via fuse setting sections H3, H4, H5, and the collector is connected to the Gnd contact. The fuse is connected to the emitter and Fmin
It may be configured to be provided between the contact point.

In order to obtain the information of the open F number, the potential of the CONT contact is made equal to the Gnd contact to turn on the transistor with the fuse connected, and the Fmin1, 2, and 3 contacts are set to the high level. Thus, in this example, the contact Fmin1 in the continuous state (1) is at L (low level), and the non-connected state (0)
Contacts Fmin2 and Fmin3 become H (high level). In other words, the configuration is the same as that one ROM memory cell is provided for each contact, and one bit of information can be stored for each contact by connecting and disconnecting a fuse connected to the base of each transistor. it can.

Table 3 shows the correspondence between the open F-number and the connection state of each contact.

In addition, the lens-side CONT contact is connected to the above-described transistor, and the lens CPU 3 is connected via a switching circuit 39.
It is configured to supply power to a Vdd terminal of 0 and a reset circuit including a resistor R, a diode D, and a capacitor C. The switching of the power supply from the CONT terminal is performed by the lens side Fmin1 terminal. After providing the information of the open F number, the CONT contact is set to H, and the Fmin1 contact is set to L, so that the lens CPU is switched. Power can be supplied.

The reset circuit has a constant time constant by a resistor and a capacitor. After the power supply voltage is stabilized after a certain period of time from the application of Vdd, the RESET terminal of the lens CPU 30 is changed from active (L) to non-active (H). It has a function of switching and starting the program of the lens CPU 30.

The Fmin2 contact on the lens side is connected to the SCK of the lens CPU 30 that outputs a clock for serial communication to the display CPU 11 on the body side.
The Fmin3 contact is connected to the DATA terminal of the lens CPU that performs serial data transfer.

The method of communication between the lens and the body is shown in FIG.

When the information of the open F number is read by the CONT terminal L from the body side as described above, the body side activates the lens CPU by setting the CONT terminal to H and the Fmin1 terminal to L to reset. When the reset is released, the body side confirms that the DATA (Fmin3) terminal of the lens CPU is H (NOT BUSY), and changes the DATA terminal from L to H to communicate with the lens CPU. Communicate start. Note that CONT and R
ESET means that once the lens CPU starts up, the state is held.

The lens CPU outputs a clock from the SCK terminal and inputs a command from the body via the DATA line. If the command requires data, an acknowledgment signal is output, and then the data is transferred.

When the communication is normally completed, the DATA terminal is temporarily set to L from the lens CPU and then set to H to transmit the command input completion to the body side.

Communication contents between the lens and the body are as shown in Table 4.

Next, the zoom operation code plate will be described.

As described above, this lens is configured so that the zoom operation can be performed by either the manual operation or the motor operation. A rotatable operation ring is provided on the outer periphery, and the rotation direction of the operation ring determines the zoom direction (tele, wide) and speed.

Although the details of the mechanical configuration are omitted, the operation ring is rotatable in the forward and reverse directions at the neutral position, and is biased to return to the neutral position when the hand is released. . Also, the operation ring is provided with four brushes,
A code plate whose conduction state is switched by sliding of a brush is fixed to a fixed ring that rotates relatively to the operation ring.

As shown in Fig. 5, the code plate has three lands on the ground land and three on the tele (FAR) side and the wide (NEAR) side.
Stepwise conductive lands are formed. In the correspondence with FIG. 3, the lands on the FAR side correspond to P24 to P26, and the lands on the NEAR side correspond to P27 to P29.

The brush that slides on the code plate has a function of conducting all the conductive lands that come into contact at the movement position with respect to the ground lands, and the lens CPU P24 to P29
, A signal of 1 when the continuity is applied and a signal of 0 when the continuity is not applied. Due to the conduction and non-conduction, seven types of signals are output corresponding to the rotation position on the FAR side and the NEAR side, respectively, at the neutral position. This signal is converted into 1-byte data, and is used in processing for selecting a zoom speed and a direction described later.

The zoom speed determined by the initial operation position and the rotation angle is shown below the code plate in FIG. The determination of the speed will be described later with reference to a flowchart, but will be briefly described here.

When the operation ring is rotated from the neutral position to the FAR side, the zoom speed is low if the rotation angle is up to F2. The amount of rotation is larger, the speed is medium for F3 and F4, and high for F5 and above. In the case of an operation from the neutral position as the operation start position before the start of driving the zoom lens, the speed can be determined using only the rotation angle as a parameter.

Next, a case where the initial operation position is not the neutral position will be described.

This power zoom device is closer to the neutral position (NT), regardless of the amount of rotation from the neutral position, so that the lens can be immediately stopped at the desired focal length at any zoom speed. When changing to the side, the zoom is stopped.

For example, when the operation ring as the operation means is rotated from the neutral position to F6 for high-speed zooming, the position of F6 is defined as the stop position. When the operation ring is continuously turned in the direction toward the neutral position to stop at the position F5 existing halfway between the neutral position and the position F6, the driving of the zoom lens is temporarily stopped. Although the zoom lens is displaced to the telephoto side, it is not known at which position on the telephoto side it is stopped.

Here, in order to zoom again to the telephoto side, when the operation ring is re-inverted from the position of F5 as the halfway stop position and stopped at the position of F6, the halfway stop position is redefined as the operation initial position, Based on the operation initial position and the stop position, the control unit controls the zoom lens at a speed different from the driving speed. When the zoom speed is determined only by the amount of rotation of the operation ring from the neutral position, the lens immediately restarts zooming at a high speed by the above-described rotation operation from F5 to F6.

However, with such a configuration, even if the lens is moved to a position short of a desired focal length at a high speed, and once stopped and then finely adjusted, the lens is zoomed at a high speed, which makes adjustment difficult. On the other hand, it is troublesome to return the operation ring to the neutral position and then re-operate.

Therefore, in the camera of this embodiment, the zoom speed is determined in consideration of not only the rotation amount of the operation ring from the neutral position but also the operation initial position, that is, the position where the zoom is started. According to such a configuration, fine adjustment near a desired focal length can be easily performed without trouble such as returning the operation ring to the neutral position.

FIG. 6 shows an example of PWM (frequency modulation) as a means for changing the zoom speed. That is, the unit of one cycle of the pulse is considered to be 1 ms. When the zoom speed is high, continuous energization is performed.
The duty is 25% at low speed. Although the ratio is not limited to this example, the rotation speed of the motor is switched by this means, and the zoom speed can be adjusted.

In general, in a zoom lens, the amount of rotation of the zoom ring and the change in focal length do not have a linear relationship. A typical example of the rotation amount-focal length curve is shown by a curve in FIG.

In such a zoom lens, even if zooming is performed at a constant speed by a motor, the focal length is slow on the wide side and rapidly changes on the tele side. From the user's point of view, such a zoom having a non-uniform focal length change is not preferable in terms of usability, and if an average change in the focal length as shown by a straight line in FIG. It will be good.

However, the curve characteristic of the focal length change in the zoom lens is generated when trying to make the rotation torque of the zoom ring constant when designing the cam of the zoom lens. If the configuration shown in a straight line is realized, the rotational torque of the zoom ring changes, which is not preferable.

In view of this, the camera of this embodiment eliminates the above-mentioned disadvantages by contriving the motor control surface while admitting the above-described curve between the rotation angle of the zoom ring and the change in the focal length. That is, even if the command for the camera is a constant speed zoom, the change in the focal length is kept constant by automatically setting the rotation speed of the motor in the control circuit to be fast on the wide side and slow on the tele side. Can be.

If the rotation angle of the zoom ring is α and the focal length is x, and the curve in FIG. 7 is represented by a function α = f (x), the differential f ′
(X) represents the rate of change of the curve at a certain focal length. The focal length inputted from the distance code plate 36 is a predetermined section 1 to
m, the representative change rate in the n-th section is f ′ (xn), and the maximum change rate in all sections is f ′ (xmax).
Then, β = f ′ (xn) / f ′ (xmax). This is the PWM determined by the speed data described above.
, The rate of change of the focal length at the same set speed can be made constant. The correction data for each section may be recorded in the ROM in the lens CPU, and data corresponding to the value detected by the zoom code plate may be extracted.

If the energization time is extremely short, the motor may stop, so it is safer to limit the correction data.

<<<< System Flowchart >> Hereinafter, the operation of the system having the above-described configuration will be described with reference to FIGS. 8 to 22. In the following description, each program of the display CPU, the main CPU, and the lens CPU will be described separately.

__ <Display CPU> FIG. 8 shows a timer routine of the display CPU.

The display CPU determines ON / OFF of the lock switch in steps (simply S. in the figure) 1 and 2, and when the lock switch is OFF, disables the switch interrupt in step 3 and then sets the state of the flag FLOCK. Then, it is determined whether or not the lens storage has been completed.

In many lenses, the entire length of the lens changes due to focusing and zooming. Therefore, it is more convenient to carry the lens when the lens is stored as compact as possible. Therefore, this camera is configured so that the lens is automatically stored in the most compact state by autofocus and power zoom when the lock switch is turned off.

However, if the lock switch is not intended to be stored, for example, if you want to temporarily leave the camera while keeping the focal length and focus unchanged, turn off the lock switch to save power and automatically store it. Is rather undesirable.

Therefore, in this camera, the lock switch is turned from ON to OF
When the automatic storage is performed by switching to F, the state before storage is stored, and control is performed so as to return to the state before storage when the lock switch is turned on again.

According to such a configuration, the lock switch can be used without any trouble whether it is intended to store the lock switch or for other purposes.

In this system, the storage and restoration for AF are directly executed by the main CPU, and the storage and restoration for PZ are directly executed by the lens CPU. However, the main CPU and the lens CPU are started only when necessary, and the power is turned off when not necessary, so the storage of the storage and return data is managed by the display CPU that is always running. .

Steps 5 to 8 are lens storage processing. For zoom, a storage command is output to the lens CPU, focal length data before storage is input, and for AF, the main operation is performed by the AF storage subroutine shown in FIG. Start the CPU and execute the process. Details on AF storage will be described later.

 When the storage is completed, the flag FLOCK is set to 0.

If the storage has already been completed, the flag FLOCK is set to 0.
Are skipped, and in step 9
P16 (CONT) is set to L, the power of the lens CPU is turned off, and the power of the LCD panel is turned off in Step 10, and then Steps 11, 12, and 13 are performed.
The timer routine is set to intermittently execute this timer routine at a cycle of 125 ms, and the processing is stopped. This process is repeated while the lock switch is OFF.

If the lock switch SWL is turned on, the display CPU determines the state of the flag FLOCK in step 14, and if the flag is 0, executes the AF return processing shown in FIG. Return to the state.

In step S16, the data input process shown in FIG. 12 is called to determine what lens is attached, and if necessary, the zoom is restored.

When the process returns to the timer routine after the subroutine, the display CPU permits the switch interruption in step 17 and proceeds to step 18.

In steps 18 to 25, when the mode switch, the drive switch, the exposure compensation switch, the up switch, and the down switch are operated, a process of changing the mode or the like according to the operation is performed to change the display.

If the mode switch or the like has not been operated, the processing of steps 11 to 13 described above is performed, and one processing is completed.

Next, the above-described AF storage and return processing will be described together with the serial interrupt processing shown in FIG.

In the storing and restoring processes, the DC / DC converter is turned ON by H of P1 and the main CPU is started, and the flags FAFREC (storage) and FAFRET (return) set in the first step are cleared by executing the serial interrupt. This is the process of waiting for the operation.

The serial interrupt process is a process executed when there is an interrupt from the main CPU.In step 30, an instruction code is input, and in step 31, the instruction code is stored in the AF.
If it is determined that it is other than the return, the process according to the instruction code is executed in step 32.

If it is the code for AF storage and return, step 3
In steps 3 and 34, it is determined whether to store or return from the state of the flag. In the case of storage, the AF storage code is output to the main CPU in step 35, and the AF required for storage is stored in steps 36 to 38.
The motor drive amount is input as the number of pulses output from the AF pulser, the flag is cleared, and the process returns to the called process. In the case of return, in step 39 the main CP
The AF return code is output to U, and the number of pulses input before storage in steps 40 to 43 is output as the number of return pulses, a return completion code is received from the main CPU, the flag is cleared, and the process returns.

The data input subroutine called in step 16 of the timer routine, as shown in FIG.
Three flags FA used for lens determination in step 50
Clear both E, FNO and FCPU.

In step 51, each port used for communication with the lens side is set to the input mode, and in steps 52 and 53, the level of the Cont contact is detected. When the Cont contact is not provided on the lens side, that is, when the AE lens as shown in FIG. 23 is mounted, the Cont contact on the body side comes into contact with the base of the mount, and the ground potential (L) is set. Therefore, in step 54, the minimum and open F
Read the number and aperture A / M switching status, and go to step 55
Sets the flag FAE indicating that the lens is an AE lens, and returns to the timer routine.

If the Cont terminal is at the H level, it is set to the L level in step 56, and the level of another contact is detected in step 57. When the lens shown in FIG. 3 is mounted, in this step, the transistor connected to the contacts Fmin1, 2, and 3 is turned on, and the open F number is input.

 Subsequently, at step 58, P16 (CONT) is set to H.

In steps 60 to 63, when P13 and P14 are both H,
Judging that the lens is not mounted, flag FN
Set O and return. As shown in Table 2, P13,1
This is because 4 (Fmax) is set so that any of them becomes 0.

The judgment in step 61 is negative when the lens is mounted.
The level of the contact 2 is detected, and if any of the detected contacts is at the L level, it is determined that the lens CPU has failed,
In step 63, the flag FNO is set and the process returns. P10-12
This is because the lens CPU keeps the H state in the communication standby state.

If a lens is mounted, P1 in step 63 '
Let 0 (Fmin1) be L. As a result, power is supplied to the lens CPU from the CONT terminal of the body, and after a predetermined interval, the reset is released and the lens CPU is activated.

In step 64, the Fmin2,3 contacts are switched from the port mode to the serial communication mode, and in step 65, the process waits until the lens CPU becomes communicable.

When the lens CPU becomes communicable, if the flag FLOCK is 0, an instruction code for PZ return is output to the lens CPU in steps 67 to 69, focal length data before storage is output, and the flag is set to 1. To the next process.

The flag FLOCK indicates that the lock switch is ON
It is set to 0 immediately after turning OFF from ON, and set to 1 immediately after changing from OFF to ON.

By the way, in step 70, an instruction code 60H is transmitted to the lens CPU in synchronization with the clock from the lens CPU.
This code is a code for receiving lens information including a switch setting on the lens side, a power hold request, and the like as shown in Table 4. In step 71, this lens information is input.

If it is determined in step 72 that there is a power hold request from the lens CPU based on the input data, P18 (VBATT) is set to H in steps 73 and 74 to start supplying power to the PZ motor drive unit 34 in the lens. Along with the lens
An instruction code 92H notifying the CPU that the power has been held is transmitted.

If there is no power hold request, an instruction code 93 notifying that power hold is to be released in step 75
H is sent to the lens CPU, and after a lapse of a predetermined time, in step 77, VBATT is dropped to L to turn off the power of the PZ motor.

In steps 78 to 81, data is input from the lens by instruction codes 61 and 33, and in step 82, the lens CPU
Flag FCPU indicating that a lens equipped with
And returns to the timer routine.

FIG. 13 shows that the interrupt processing shown in FIG. 18 is executed when the photometry switch and the release switch are turned on while the SWS, R interrupt is permitted in the timer routine.

When this switch interrupt processing is entered, first, step 90
After prohibiting the switch interrupt again, the power of the main CPU is turned on in step 91, and the serial interrupt is permitted in step 93.

While the lock switch SWL and the photometering switch SWS are both ON, the processing of steps 91 to 97 is repeated to input the ever-changing information from the lens ROM and the lens CPU,
The same mode, drive, and exposure correction setting change processing as that shown in steps 18 to 25 of the timer routine is performed.

Either lock switch SWL or photometric switch SWS is OFF
Then, in steps 98 to 101, the power of the main CPU is turned off, the timer is set, the timer interrupt is permitted, and the processing is stopped.

__ <Main CPU> Next, a program installed in the main CPU will be described with reference to FIGS. 14 and 15.

When the display CPU sets P1 to H and the DC / DC converter is turned on, the power of the main CPU is turned on and the processing is started.

In step 110, initialization is performed. In step 111, the AF storage return code is sent to the display CPU, and then the instruction code from the display CPU in step 112 is input.

In steps 113 and 114, it is determined whether the instruction code is related to AF storage or AF recovery. If it is stored, in steps 115 to 118, AF
The motor is driven until the lens reaches the storage position, and the number of pulses output by this drive is used as return information for display.
It outputs to the CPU, outputs a power hold OFF request in step 119, and ends the processing. If the instruction code is for return, the display
The AF motor is driven by the number of pulses input from the CPU to return the focus state of the lens to the state before storage, and step 12
Outputs AF return completion code at 4.

If the instruction code is neither storage nor return, in step 125 the metering switch or release switch
Judge whether or not N.

If any switch is OFF, step 119
Requests the display CPU to turn off the power hold, and terminates the process.

If the photometry switch or the release switch is ON, the photometry A / D and DX information are input from the A / D circuit 15 and the DX input circuit 13 in steps 126 to 29, respectively, and the lens data and the set Shutter speed Tv,
The aperture Av is input from the display CPU, and Tv and Av are calculated.

In step 130, the main CPU transfers the calculated information of Tv and Av to the display CPU for displaying on the LCD panel.

Subsequently, in step 131, the release switch is turned ON / OF.
Judge F.

When the release switch is ON, if the AF is manual, the flag FAF is set to 0, the process proceeds to "B" in FIG. 15, and the release process is performed.
Is set to 1 and it is determined in step 138 whether focusing is priority or release is priority. If release is priority, the process proceeds to "B". The auto / manual determination of AF is performed based on the lens switch SWAF3 and the body SWAF2, but the setting of the lens switch is given priority.

If the release switch is OFF, or if the AF is automatic and the focusing is prioritized even when the release switch is ON, the processing for distance measurement proceeds.

In steps 139 and 140, the distance measurement data from the CCD processing circuit 18 is input to determine the amount of defocus, and the process proceeds to "A" in FIG.

If it is determined in step 141 in FIG. 15 that the camera is in focus, it is determined in step 142 whether the camera is in focus or release priority. In the case of focusing priority, while the photometry switch is ON in steps 142 and 143, wait for the release switch to be ON and lock the focus,
When the release switch is turned on, the process proceeds to the release in step 146. If the release priority, go to step 145,
If the release switch is ON, the camera immediately enters the release mode.

In step 146, the set shutter speed,
A shutter release is performed at the aperture. When the release is completed, the main CPU drives the wine motor to wind up the film in step 147. When the drive C, that is, the continuous shooting mode, is immediately returned to the 14th “C” to proceed the processing, Steps if in shooting mode
At 149, the process returns to "C" after the release switch is turned off.

If it is determined in step 141 that the camera is not in focus, or if the photometry switch is turned off with priority on focusing and the release switch is turned off with priority on release, focusing is automatically performed by the flag FAF in step 150. In step 151-154, the AF motor is driven by the number of AF motor drive pulses calculated based on the defocus amount. If the focusing is manual, steps 151-154
And returns to “C” in FIG.

__ <Lens CPU> Next, the operation of the lens CPU will be described with reference to FIGS. 16 to 21.

FIG. 16 is a main flowchart of the lens CPU.
The lens CPU has a CONT contact,
After the Fmin1 contact is set to H, the reset circuit operates and the reset is released to start.

After disabling all interrupts described later in step 200, the lens CPU performs initialization in step 201, and forms a loop of steps 202 to 215.

In step 202, each switch provided on the lens,
Read the data of distance code plate and zoom code plate,
In step 203, these data are stored in the RAM, and processing is performed based on the data.

In steps 204 to 208, it is determined whether the zoom is to be performed electrically or manually by the first PZ switch of the lens. If the zoom is to be performed manually, the flag FPZ is set to 1 if any switch is ON, and the power hold is performed. The process proceeds to step 209 with the request bit set to 1.

If the zoom is performed manually, or if all the switches are OFF even in the power zoom, the process proceeds to step 209 with the power hold request bit set to 0 in step 208-2.

In steps 209 to 211, when the constant image magnification control is selected by setting the second PZ switch, the flag FCON
ST is set to 1, and this flag is set to 0 when not selected.

After the above-described flag setting processing, a serial interrupt described later is permitted in step 212, a timer of 125 ms is set and started in steps 213 to 215, the timer interrupt is permitted, and the processing is stopped until there is an interrupt.

_ <Lens CPU Serial Interrupt Processing> FIG. 17 is a flowchart showing the serial interrupt processing of the lens CPU which is executed when a serial interrupt is issued from the body display CPU and which inputs and outputs data and commands. .

Here, first, in steps 220 and 221, two timer interrupts and a serial interrupt are prohibited until this processing is completed, and in step 222, a communication clock is output and an instruction code from the body is input. H and L of each contact at this time are as shown in FIG.

Step 223 and subsequent steps are routines for executing processing according to the type of instruction.

First, in step 223, it is determined whether the 2/4 code is correct. As shown in Table 4, the instruction code is
Since 2 bits are always set to 1 and 2 bits are set to 0 among the bits, if this is not the case, no processing is executed as an instruction code input error and step 24 is executed.
At 9,250, enable the interrupt and return to the main routine.

If the 2/4 code is correctly determined, it is determined in step 234 whether the instruction code indicates a data request. If it is a data request, the requested data is set in the RAM in step 235, this is output to the display CPU in step 236, and the process proceeds to step 249.

If the content of the instruction code is not a data request, it is determined in step 237 whether the instruction code is 90H. If it is 90H, which means PZ storage, in step 238, the current focal length information is output to the display CPU as data at the time of return, and the PZ motor is set so that the lens is set to the storage position in step 239. After driving, the process proceeds to step 249.

If the instruction code is not 90H, it is determined in step 240 whether the instruction code is 91H. If it is 91H, which means PZ return, the focal length information output during storage in step 241 is input from the display CPU, and the PZ motor is driven in step 242 to set the lens to the focal length before storage. After that, the process proceeds to step 249.

If the instruction code is not 91H, it is determined in step 243 whether the instruction code is 92H. If it is 92H, it means that the power hold of the VBATT for the PZ motor has been turned on on the body side.
After setting the PH bit to 1 and starting a 10 ms timer described later in steps 245 and 246 to permit a 10 ms interrupt, the process proceeds to step 249.

If the instruction code is not 92H, it is determined in step 247 whether the instruction code is 93H. If it is 93H, it means that the power hold has been turned off.
Proceed to 49.

If the instruction code is not one of the above, step
At 249 and 250, the interrupt is permitted and the process returns to the timer routine.

__ <10 ms Timer Interrupt Processing> FIG. 18 shows a timer interrupt processing of the lens CPU. This processing is performed during the serial interrupt as described above.
When a 10ms interrupt is enabled, it is executed at 10ms intervals,
This is a process for executing power zoom control.

In this process, serial interrupts, 125 ms interrupts, and 10 ms interrupts are prohibited in steps 260 and 261.

In step 262, a subroutine for endpoint detection shown in FIG. 19 is called. The end point detection processing is processing for determining that the zoom lens has hit the telephoto end or the wide end.

In the end point detection processing, in step 280, the flag FPULS
The state of E is determined, and if the PZ pulse does not change and this flag is 0, the counter CPUL is incremented in step 281 and it is determined in step 282 whether or not the counter CPUL becomes 10 or more. The flag FPULSE is a flag that is set to 1 when the PZ pulse changes.

If it is 10 or more, the flag FBRK for applying a brake to the PZ motor is set to 1 in step 283, the flag FPULSE is cleared in step 284, and the routine returns. If it is less than 10, skip step 283 and execute skip 284. This counter CPUL is cleared in step 285 when the PZ pulse changes and the flag FPULSE becomes 1.

Endpoint processing is executed every 10 ms, so P
If there is no change in the Z pulse, the flag FBRK is set to 1 at the end point, and it is determined that the lens has hit the end point.

When the process returns from the end point process to the 10 ms timer interrupt process, the state of the flag FCONST is determined in step 263. The flag FCONST is set in accordance with ON / OFF of SWPZ2 in the main routine described above. If the flag is determined to be 1, in step 264, constant image magnification control is executed. What is image magnification constant control?
Control that changes the magnification of the lens so that the size of the subject image on the image plane is kept constant even when the distance between the subject and the camera changes. Calculate the change in magnification from
This is performed by controlling the PZ motor by converting it into a drive pulse of the PZ motor. The details of this process will be omitted.

If the flag FCONST is 0, the zoom operation code is read in step 265, and a speed direction selection subroutine described later is executed in step 266 to determine the zooming direction and speed.

In step 267, it is determined from the state of the flag FBRK whether or not to apply a brake to the PZ motor. If not, a zoom code corresponding to the focal length is read from the zoom code plate in step 268, and accordingly, step 269 is performed. Is applied to the PWM control value by the speed correction process. Flag FBR
K becomes 1 when the lens abuts on an end point and when zoom stop is instructed by operating the zoom operation ring.

As described above, this camera controls the rate of change in image magnification to be constant by adjusting the rotation speed of the motor. The speed correction process is a process for realizing this. In the speed correction processing, correction data is set in step 300 as shown in FIG. As described above, the correction data is such that the representative change rate in the n-th section is f '(xn), and the maximum change rate in all sections is f' (xmax).
Is a value represented by β = f ′ (xn) / f ′ (xmax). By multiplying this by the PWM energizing time determined by speed data described later in step 301, a PWM energizing time for making the image magnification change constant can be obtained. In step 302, a predetermined limit is applied to the calculated value in order to prevent the motor from stopping when the calculated energization time is extremely short.

When the speed correction process is completed, the driving of the PZ motor is started in step 270, a 10 ms timer is set and started in step 271, and all interrupts are permitted in steps 272 and 273 and the process returns.

If the flag FBRK is set to 1, step
At 274, the brake process shown in FIG. 21 is executed to stop the rotation of the motor.

In the brake process, the motor is braked in step 310, and the image magnification is not fixed in step 312, 313,
Moreover, when the flag FPZ is 0, the brake time is set in the same manner as in the detection of the full score. The flag FPZ is set to 1 when driving the zoom in the speed direction selection processing described later.

In step 314, the counter CBRK for measuring the brake time is incremented, and in step 315, the counter CBL
Judge whether K is 10 or more. If it is not less than 10, the flag FBRK is cleared to 0 in step 316 and the routine returns. If it is less than 10, the process skips step 316 and returns.

When the flag FPZ is set to 0, the counter CBRK is cleared in step 317.

Therefore, when the flag FBRK is set to 1, the 10 ms timer interrupt process proceeds from step 276 to step 274, so that the brake is applied for 10 ms.

When the brake process is executed and the flag FBRK becomes 0, the power hold request bit is set to 0 in step 276, the 10 ms timer interrupt is prohibited in step 277, and the 125 ms timer interrupt and serial interrupt are enabled in steps 278 and 273. And return.

FIG. 22 shows a speed direction selection subroutine called in step 266 of the lens CPU 10 ms timer interrupt process. This process is a process for determining the zoom direction and speed according to the operation state of the zoom operation ring, and is a specific method for realizing the determination shown in the lower part of FIG.

The 6-bit data input from the P24 to P29 terminals of the lens CPU is converted into a 1-byte code according to the correspondence shown in Table 5 below.

In this process, a variable for storing the conversion code in the RAM is set as follows.

Latest code DN DNH: Upper 4 bits DNL: Lower 4 bits Previous code DO DOH: Upper 4 bits DOL: Lower 4 bits Start position code DS DSH: Upper 4 bits DSL: Lower 4 bits Input to DN and if upper 4 bits are 0,
That is, if the flag is in the neutral position, the flag FPRK is cleared in steps 322 to 324, the flag FBRK is set to 1, and DN is
And return.

If it is not at the neutral position, the flag FPZ is set to 1 in step 325, and the driving direction is determined in steps 326 to 331. DNH
When DOH is equal to DOH, that is, when the direction of the zoom ring has not been switched, it is determined whether the zoom ring has been operated toward the end point or toward the neutral side, and the operation toward the neutral side is determined. If there is, at step 323 the flag FBRK is set and the process returns.

If the direction has been switched, the start position is set to the neutral position, and the process proceeds to step 332 and subsequent speed settings.

If the direction has not been switched and the operation toward the end point or the position of the zoom operation ring has not been changed,
It is determined whether driving is in progress based on whether the flag FBRK was set to 1 in the previous process. If the flag FBRK was previously set to 1, if there is no change in the code, step 32
After returning via 3,324, if there is a change in the code, the previous code is set as the code of the start position, and the speed setting is started. If the flag FBRK is not set to 1 in the previous processing, the speed setting is directly started.

Steps 332 to 345 are for setting the speed based on the start position and the amount of rotation of the zoom operation ring as shown in the lower part of FIG.

If the start position is the neutral position, and if the rotation position of the zoom operation ring is larger than 4, the speed data DSP is executed at step 348.
If ED is set to high speed and it is between 2 and 4, step 34
If it is 7 or less, the low speed is set in step 346.

If the start positions are F1 and N1, the rotation speed of the operation ring is higher than 5; the speed is 3;

If the start position is F2, N2, the rotational speed of the operating ring is higher than 6, the speed is high if it is between 4 and 6, and if it is 3 or less, the speed is low.

If the start position is F3, F4, N3, N4, if the rotation position of the operation ring is larger than 6, high speed, if between 5 and 6, medium speed,
If it is less than 4, the speed is low.

If the start position is F5, N5, the speed is high if the rotation position of the operation ring is larger than 6, and if the rotation position is 5 or less, the speed is low.

When the start position is F6, F7, N6, N7, only low speed is set even if the rotation position changes.

When this speed setting is completed, the data DDI
The driving direction is set in RC, the flag FBRK is cleared in step 350, the DN code is substituted in DO in step 351 and the routine returns.

Note that with the above control, when the detent operation ring is rotated from F6 to F7 or from N6 to N7 with the zoom stopped, the operation ring immediately reaches the end point, and the speed is set to only low speed. Not done. Therefore, while the section of F7, N7 is set extremely narrow and the section of F6, N6 is set narrower than other sections, when the operation ring is rotated to the neutral side from F7, N7, F5, It is easy to enter N6, and it is possible to select between high speed and low speed when it is turned again to the end point side.

[Effect] The electric zoom device of the present invention can be operated in both directions based on a neutral position as a boundary between telephoto and wide in a state before the start of the zoom drive, and operates the operation start position before the start of the zoom lens drive. An operation unit that defines an initial position, and defines a stop position when operated and stopped in any one of the tele and the wide directions from the neutral position, the operation initial position and the stop position And controlling the driving direction and the driving speed of the lens driving unit based on the operation of the zoom lens by operating the operation unit in the one direction, and inverting the operation unit in the direction toward the neutral position after driving the zoom lens. And when stopped in the middle of the neutral position and the stop position, the drive of the zoom lens is temporarily stopped,
When the operating means is again stopped by performing the re-inverting operation in the one direction, the middle position of the operating means is redefined as an initial operation position, and the zoom lens is defined based on the initial operation position and the stop position. Control means for controlling the driving speed at a speed different from the driving speed, so that even when the operating means is largely operated in a direction away from the neutral position to drive the zoom lens at a high speed, the usability is good, This has the effect of allowing fine control of the position near the position where the zoom lens is to be stopped.

[Brief description of the drawings]

1 is a block diagram showing an embodiment of a camera system according to the present invention, FIG. 2 is a circuit diagram of a body, FIG. 3 is a circuit diagram of a lens, FIG. 4 is a command between the body and the lens, FIG. 5 is a timing chart showing data communication, FIG. 5 is an explanatory diagram showing the correspondence between the pattern of the zoom operation code plate and the zoom speed by operation, FIG. 6 is a timing chart of PWM control for changing the zoom speed, and FIG. 8 is a graph showing the relationship between the rotation angle of the zoom ring and the change in the focal length, FIGS. 8 to 13 are flowcharts showing the operation of the display CPU of the body, and FIGS. 14 and 15 are main diagrams of the body.
16 to 22 are flowcharts showing the operation of the CPU, and FIGS. 16 to 22 are flowcharts showing the operation of the lens CPU. 1: Camera body 2: Lens 10: Main CPU 11: Display CPU 30: Lens CPU

Continuation of front page (58) Field surveyed (Int.Cl. ⁶ , DB name) H04N 5/222-5/257 G02B 7/08

Claims (1)

(57) [Claims] 1. An electric zoom apparatus comprising a lens driving means for changing a focal length of a zoom lens, wherein in a state before zoom driving is started, operation is possible in both directions based on a neutral position as a boundary between telephoto and wide. The operation start position before the start of driving the zoom lens is defined as an initial position, and the operation start position is defined as a stop position when the zoom lens is operated and stopped in one of the telephoto and the wide directions from the neutral position. Operating means, controlling a driving direction and a driving speed of the lens driving means based on the initial position and the stop position, and operating the operating means after operating the zoom lens by operating the operating means in the one direction. When the inversion operation in the direction toward the neutral position side and stopped halfway between the neutral position and the stop position, the drive of the zoom lens is temporarily stopped, And when the operating means is re-inverted in the one direction and stopped, the midway stop position of the operating means is redefined as an initial position, and the zoom lens is moved based on the initial position and the stop position. An electric zoom device having control means for controlling at a speed different from the driving speed.